Mould spores allergy
Allergy to airborne mould spores, worse in damp conditions.
About mould spores allergy
Mould spores are the microscopic reproductive particles released by moulds and fungi, which drift in the air both outdoors and indoors. Outdoor moulds such as Cladosporium and Alternaria peak in warm months and during late summer and autumn, while indoor moulds thrive year-round wherever there is damp, condensation or water damage. When a sensitised person breathes in the spores, the immune system reacts to their proteins through an IgE-mediated allergic response. Mould allergy is less common than pollen or dust mite allergy, but it is well recognised and can be persistent, especially in damp homes.
The usual presentation is allergic rhinitis, with sneezing, a runny or blocked nose and itchy, watering eyes, which may be seasonal for outdoor moulds or continuous where indoor damp is the source. Mould allergy has a notable link with asthma and can trigger cough, wheeze and chest tightness, sometimes contributing to harder-to-control asthma, and it may aggravate eczema. Reactions are seldom life-threatening, but they can disturb sleep and daytime function, and asthma flares always merit attention.
Management centres on reducing damp and mould: fixing leaks and condensation, ventilating kitchens and bathrooms, drying wet areas promptly, and cleaning affected surfaces, while limiting outdoor exposure when spore counts are high. Diagnosis uses skin-prick or specific-IgE tests. Treatment follows the usual ladder of antihistamines and steroid nasal sprays, with immunotherapy considered for selected cases. See a GP if symptoms are persistent, if damp in the home is a problem, or if asthma is worsening.
Common triggers
- Damp walls and bathrooms\nRotting leaves and compost\nHumid indoor air
Symptoms
- Sneezing and a runny or blocked nose
- Itchy, red or watery eyes
- Itchy throat, nose or ears
- Coughing or wheezing
- Worsening of asthma
Avoidance & management
- Reduce exposure to the trigger where possible
- Keep windows closed during high-exposure periods
- Use air filtration and wash bedding regularly
- Shower and change clothes after exposure
- Use prescribed antihistamines, nasal sprays or preventers
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.